E. coli formed biofilm on the surface of PLA and PHB with PHMG derivatives (Fig. 3). The amount of biofilm on PLA and PHB with APHMG was similar to the amount observed on control samples (PLA and PHB without PHMG derivatives). In contrast, W-PHMG inhibited biofilm formation by E. coli on both PLA and PHB composites. At higher concentrations, the inhibitory effect of this PHMG derivative on biofilm formation by these bacteria was stronger. The